v3: refactor request/response mocking to use a unified MockDoer API #487
Description
Currently, the test mocks for the Tarantool client use separate types for
mocking requests and responses (e.g., a standalone ResponseMock). This
makes test setup verbose and exposes internal implementation details that
users shouldn’t need to manage.
We want to simplify and unify the mocking interface by introducing a single,
fluent MockDoer that lets tests declaratively define expected responses
while automatically capturing incoming requests.
Proposed API
Replace the current approach with a MockDoer interface like this:
type MockDoer interface {
// Add a successful response with just payload data
AddResponseOk1(data []interface{}) MockDoer
// Add a successful response with explicit header and body
AddResponseOk2(header tarantool.Header, body io.Reader) MockDoer
// Add an error response (e.g., network or protocol error)
AddResponseError(err error) MockDoer
// Return all requests that were sent to this mock during the test
Requests() []tarantool.Request
}This design:
- Uses method chaining for easy setup
- Hides low-level response construction (e.g., no need to build full
Responsestructs manually)
Example Usage
mockDoer := mock.NewDoer().
AddResponseOk1([]interface{}{"OK"}).
AddResponseError(io.EOF)
client := tarantool.NewClient(mockDoer)
_, err := client.Call("some.func", nil) // succeeds
_, err = client.Call("another.func", nil) // returns io.EOF
// Later in test:
assert.Len(t, mockDoer.Requests(), 2)
assert.Equal(t, "some.func", mockDoer.Requests()[0].(tarantool.CallRequest).FunctionName)Related links and repos
- convenient powerful mocks: https://github.com/DATA-DOG/go-sqlmock